Glossary of Blacksmithing and
Metalworking Terms

Definitions of words as used in metalworking

This is one part of a larger metalworking glossary project that also includes an International Glossary as well as linking to illustrations and charts as needed.

See Alphabet Soup for blacksmithing and metalworking acronyms.

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1/7th rule
The draw rate of acetylene cylinders. This says that given the volume of gas stored in the cylinder at normal pressure you should only draw gas at 1/7 that volume per hour. This also means that under maximum normal use you should expect 7 hours of gas supply from an acetylene cylinder. Example: Using a 140 cubic foot cylinder gas should be drawn a a maximum rate of 20 CFH (Cubic Feet per Hour).

See Gas Facts

acquisititus    ac· quiz' i · t ¯ i' tis,
a. An obsessive need to acquire everything associated with one field of interest. Particularly afflicting Blacksmiths, Computer Geeks and other tool, hardware and software collectors. Origin, JOSH GREENWOOD, one of the first to recognize the symptoms in himself.
JOCK DEMPSEY - March 27, 1987      

A mixture of two or more metals such as bronze which is made of copper and tin. Alloys are not compounds but mixtures of metals dissolved into each other which crystallize into separate crystals on solidifying. Alloys often have properties much different than their constituents. Greater strength, hardness or different melting point. Density is almost exactly the sum of the ratio of the densities but not quite. Almost all metals and alloys have small amounts of "trace elements" that are impurities but sometimes contribute to the alloy's properties.

A heavy object of durable material that resists the inertia of a hammer or mechanical ram while supporting material struck by the moving part. The earliest anvil was a heavy stone used to resist the movement of an object struck against it or struck while supported on it. This is such a basic tool that both birds and monkeys have been observed using a stone as an anvil and probably predated man's use of tools. This would make the anvil the FIRST tool.

The modern blacksmith's anvil is a sophisticated tool developed over millennia of tool making. Like many iron age tools it has roots in the bronze age. The modern blacksmith's anvil has a hard heat treated tool steel face and a durable soft iron or steel body. The shape and size varies with purpose and regional stylistic preferences. The average blacksmith's anvil weighs 120 pounds (55kg). Universally most anvils have a flat horizontal face and a conical horn or "beak", but there are also hornless styles such as the sawyers anvil. Most anvils have a round punching hole and all modern smithing anvils have a square tooling hole called a hardy or hardie hole.

Other anvil features are less standardized such as:

  • Square sectioned pyramidal horn of the European or Leige's pattern.
  • Step and cutting table of the English and American pattern
  • Extra punching holes graduated in size (Hofi and Euroanvil).
  • Carriage maker's side table.
  • Sloped off-hand side of the old central European anvils
  • Upsetting block
  • Turning lugs or cams (farrier's only)
  • "Clip" horns (sharp edged bulges on the horn - farrier's only)
  • Chainmaker's "Dolly" holes (1 or 2, square through side of body)
  • Knifemakers dovetail and plain tooling slots.

See Selecting an Anvil.

Generally an apprentice is a novice or new student of a subject. The definition of "apprentice" has changed with time and still varies with the place or occupation. In the past, it meant one that was legally bound to a Master in the arts as a student for a prescribed period (usually 7 years). In exchange for their labor an apprentice was given an education in the craft and basic tools of the trade. Today an apprentice may be any student learning from someone of greater knowledge. Upon graduation an apprentice becomes a Journeyman.

There have been and still are laws in some places defining and regulating the relationship between apprentice and master. In some countries it is illegal to teach a trade or take on an apprentice, unless you have master's papers. However, in many places, such as the United States, the old apprentice system is an institution of the past.

See Apprenticeships in Blacksmithing.

The word "smith" is said to come from the word "smite" or "to strike" as with a hammer. In modern terms this has been stretched to "make". Black refers to the color of iron and steel after it has been heated and cooled. The surface has a covering of black oxide called scale. Thus the blacksmith is one who strikes the black metal or the maker of things from the black metal.

The whitesmith works with iron or steel that has had the scale removed and traditionally was a decorator or finisher of forged iron work using scrapers, chisels and files. The modern whitesmith may also be one who works with zinc and aluminium by hand.

Today we have the "Artist Blacksmith" and the "Hobby Smith". These are taken from the German where they distinguish between the type of smiths.

These words go back to the earliest times and have similar translatable roots and often sounds in many languages.

English blacksmith, German (der) Schmied, Swedish smed, French (le) forgeron, Italian fabbro, Spanish (el) herrero; (el) forjador, Africaans smid, Portuguese ferrarius, Hungarian patrokolokovacs.

The ancient process, or name of the place, of making wrought iron. In this process charcoal fuel and a flux (usually limestone) was used to smelt iron from iron ore. When the iron melted and became a porous mass but before it fully liquefied and ran into the bottom of the furnace, the brightly glowing mass (the bloom) was removed and hammered (wrought) to consolidate the bloom into a solid mass of iron. In the process some of the flux and ore remained in the iron giving it the characteristic wood like grain.

Bloomeries usually used a tall "Catalan" type furnace with an air blast provided by a pair of huge water powered bellows. The same water power usually ran a trip hammer that was used to forge the iron.

Also known as "gun blue" is a chemical process that produces a a blue or blue black oxide finish on steel. The blues are often known as "niter" blues because of the use of nitric acid in the process. These finishes retard rusting but require constant maintenance, cleaning and oiling, to prevent rust in the long term.

For details see Firearm Bluing and Browning by R.H. Angier, or Machinery's Handbook for formulas with less detail.

See browning

bluing-in, machinists blue
A process used to create fine fits or make flat surfaces using a thin transferable surface coating. Traditionally machinists and instrument makers have used Prussian Blue (iron ferrocyanide) artists paint. It is applied to one of two surfaces (generally the smoother or reference) to be mated and the two surfaces are placed in contact. The blue transfers to the high spots of the surface to be flattened. Those high places are scraped, filed or sanded down and the process is repeated as many times as necessary to achieve the desired surface. In the modern machine shop this process has been mostly replaced by precision machining and grinding.

Sodium tetraborate, Na2B4O7. A soft white mineral found in old lake bed deposits. Borax is used as a flux for brazing and welding. It is used as forge welding flux by blacksmiths and in coated arc welding rods. Also sold under the trade name Solubor® as a boron fertilizer.

See Borax

An alloy made primarily of copper and zinc with trace elements typically including silicon and iron. Brass is a golden yellow and weathers to a green but is relatively corrosion resistant. It can be very ductile but is often used to make castings.

See Brass and Bronze FAQ

An alloy made primarily of copper and tin with trace elements typically including silicon and iron. Bronze is one of the oldest of the known alloys and was the first commonly used metal strong enough for tools and weapons was bronze, thus the "Bronze Age". Bronze is a reddish color and weathers to a green but is relatively corrosion resistant. Additions of beryllium make it hard enough to be used for springs and tools such as wrenches and hammers.

See Brass and Bronze FAQ

A process of controlled rusting used to produce a rust resistant oxide finish. Historically this was used by early gunsmiths and other craftsmen to produce a dull rust resistant surface on guns, tools and other items. The iron oxide finish requires oiling to prevent further rusting.

See bluing

Element number 6, both metal and non-metal. Symbol C. Crystalline forms are diamond and graphite. Charcoal and coke are nearly pure carbon fuels. Carbon molecules are the basis of all life. The addition of carbon to iron makes steel. Too much carbon makes steel into brittle cast iron. See our Coal and Charcoal FAQ

Density 2.25 g/cm3, .0813 lbs/cuin, diamond = 3.53 g/cm3, .1275 lbs/cuin,
graphite = 2.51 g/cm3, .0907 lbs/cuin.

Los Alamos National Laboratory periodic table entry carbon

A surface hardening technique used on ferrous metals. The iron absorbing carbon in a salt bath or by the application of carbonaceous salts and heating with a torch. Cyanide salts are used but are being replaced due to its toxicity.
See case hardening

case hardening
A process where carbon is absorbed into the surface of a piece of low carbon steel or wrought iron producing a hard "case". There are two basic methods. 1) Sealing the piece of iron in a container packed with charcoal and heating the whole for a period of time. The piece is quenched directly upon removal from the case hardening box. 2) Salt bath treatment or carbonnitriding where the piece is emersed in a molten salt bath such as cyanide salt for a period of time, removed and quenched.

The depth of the case varies with time and temperature and is approximately the same for both methods.

Carbonnitriding starting with low carbon steel (SAE 1008):

1 hour @ 1425 to 1450°F (734 to 788°C) results in a case .004" (0.1mm) deep.
4 hours @ 1425 to 1450°F (734 to 788°C) results in a case .011" (.28mm) deep.

1 hour @ 1600 to 1625°F (871 to 885°C) results in a case .015" (.38mm) deep.
4 hours @ 1600 to 1625°F (871 to 885°C) results in a case .030" (.76 mm) deep.

Heat Treaters Guide, 1982, ASM, p.25 chart (referencing Metals Handbook 8th ed., Vol 2, ASM.)

A trade mark case hardening compound. New formula is cyanide free. The powdered Casenit is sprinkled on heated iron or steel and melted with a torch. After a period of time the part is quenched hardening the surface that has absorbed some extra carbon.
See case hardening and carbonnitriding

cast iron
Also called pig iron. Covers a large group of irons with 2% or more carbon. The high quantity of carbon makes cast iron brittle and suitable for forming only by casting and machining. It cannot be forged. The lack of ductility, high stiffness and deadening qualities makes cast iron a superior material for machinery beds and frames.

Average density of cast iron, 7.377 g/cm3, .2665 lbs/cuin, 460.51 lbs/cuft
Mechanical Properties

The metric standard scale for measuring temperature. A scale where the fixed points are the temperatures at standard (sea level atmospheric) pressure of ice in equilibrium with water (0°C) and water in equilibrium with steam (100°C). The difference being divided into 100 parts. Formerly known as the centigrade scale, the name was changed in 1948 to avoid confusion with the hundredth part of a grade (an unit of angular measurement also in degrees). The name is taken from Anders Celsius (1701-44) who devised the inverted form of this scale where the ice point = 100° and the boiling = 0°.

Cerrocast, Cerrobend, Cerromet
Low temperature melting alloys from 117°F : Often misspelled as Ceracast, Cerabend or Ceramet instead of Cerro... .

Cerro Metal Products Co., Alloy Dept.
Now Bolton Metal Products
2022 Axemann Road
Bellefonte, PA 16823-8142
Phone: 814-355-6217

Low Melting, Fusible, Non Shrinking, For Tube Bending, Work Holding, Pattern Making, Die Mounting, Medical Shielding Devices, Mold Making, Forming Dies For Sheet Metal Parts, Proof Casting.

In the past these folks made alloys that would melt at body temperature. A common use is making unusual shaped cores in plastic or ceramic pieces. There are also non-shrinking and expanding alloys used to bed in parts such as ways in machine tools. The ways are precision aligned and then the alloy poured around end of the ways in a pocket (usually in a casting) to lock it in place. Indium Corporation of Utica, New York makes a similar product to Cerrobend (Indalloy 158).

Charred wood or other dense organic matter used as fuel. Charcoal is manufactured from wood by heating it in a controlled fire with insufficient oxygen to completely burn the wood that drives off the water, volatiles and light elements. The result is mostly porous carbon. Charcoal burns hot and clean leaving a light white ash. For thousands of years it was used as fuel for everything including smelting and melting metals, fueling blacksmith forges and cooking.

"Charcoal" briquettes sold for barbecues are made from a mixture of ground charcoal, sawdust and bituminous coal bonded with a starch glue. It is generally not suitable for fueling blacksmith's forge. Real charcoal is sold in bulk for use in restaurants.

Charcoal is also made from charring bones. This produces "bone black" used in artists paints and is also recommended for case hardening

An organic mineral product resulting from the accumulation of organic material in peat bogs millions of years ago. Geologic process compressed the peat into a carbonaceous material. Coal varies in quality due to the inclusion of non-organic materials such as sand, silt and clay. These determine the character of the coal ash and clinkers. Coal also contains variable quantities of volatile hyrdocarbon compounds and sulfur. This large number of variables means coal can be in any number of grades ranging from peat, to nearly pure carbon to slate.

Bituminous coal is a soft coal resulting from the volatile content. Anthracite is hard coal that is low in volatiles.

See our coal and charcoal FAQ

cold shut
A fold in rolled or forged metal closed (shut) by the process but not welded. A cold shut is the same as a crack except it has been caused by bad forging or rolling practice. Commonly mispronounced "cold shunt".

Element number 29, symbol Cu, a metal (Latin, cuprum). A red ductile metal occasionally found in its native state. Copper is an excellent conductor of heat and electricity only second to silver in electrical conductivity. Copper is the primary metal in the alloys brass, bronze and monel. In small amounts copper is used to make aluminium, silver and gold harder. As small amount ads corrosion resistance to steel.

American pennies, before 1983 were actually bronze, not copper. Copper is too soft and would wear very rapidly. New American pennies are zinc with a copper coating.

Average density of copper, 8.96 g/cm3, .3237 lbs/cuin, 559.35 lbs/cuft

Los Alamos National Laboratory periodic table entry copper
Copper Development Association

One who works copper, brass or bronze with a hammer. The oldest of the smiths who worked metals smelted from ore.

See Blacksmith

ductile iron
Also called "malleable iron". A ductile product made from cast iron by inoculating cast it with magnesium in the crucible or the mold as is it cast. The magnesium causes the excess carbon to form graphite nodules leaving the surrounding iron low enough carbon to be ductile. Many items that we identify as cast iron are often ductile iron. Besides being very tough it can also be arc welded.

Average density of ductile iron, 7.27 g/cm3, .2626 lbs/cuin, 453.85 lbs/cuft

The common standard scale of temperature measurement. Invented by the German scientist Gerald Daniel Fahrenheit (1686-1736) inventor of the mercury thermometer. Fahrenheit set 0° at the lowest temperature he could measure (freezing point of salt water) and 96° at human body temperature. Later the range was defined with the ice point at 32° and the boiling point at 212° (a difference of 180°, a geometric reference). The ice point is still the standard by which most temperature measurement devices are calibrated.

flame hardening
A surface hardening technique using an intense heat source followed by a water quench. Typically, ganged oxy-acetylene heating tips are used to heat the surface of a wide area. Running water quenches the heated area as the process moves across the surface. It is a common method of hardening gear teeth leaving a soft tough root and hub while producing a hard wear resistant surface.

A flux is a chemical that dissolves metal oxides for the joining of the metals by soldering, brazing or welding. Secondarily the flux may protect the metal from further oxidation while heating.

For forge welding the most common flux is borax.

In some instances powdered metal is added to the flux to provide easier joining. Powdered iron is used in some blacksmithing fluxes. Tin powder is used in some rosin based soldering fluxes.

noun, 1. A device or place to hold an intensified fire for the purpose of metalworking. 2. A place, building or shop where a forge is used. verb, to forge, forging, the act or process of shaping heated metal by hammering. Forging, noun, an item made by the process of forging.

A typical forge has a forced air source such as a bellows or blower to intensify the fire, a refractory lining or enclosure to hold the fire and a chimney or vent. Fuels include charcoal, mineral coal, heating oil or diesel fuel, propane (LPG), butane or natural gas (NG).

One who works gold and gold alloys with a hammer. Probably the oldest of the smiths as gold is commonly found in nuggets (native metal) ready to work.

See Blacksmith

hardy or hardie
A short square shanked chisel that fits in the square "hardy hole" of an anvil. Some have thin blades for hot cutting, some thick for cold cutting and specialized hardies have curved blades for rounding the heal of a horseshoe. Hardy is an old English term of uncertain origin.

The hardy hole is named after the tool. Other tools that fit the hardy hole are mistakenly called hardy (or hardie) tools. These are not hardies, they are anvil tools, set tools and square shanked tools (depending on your country and local terminology).

There have been suggestions that it is related to stoutness as in a "hardy variety" but this is false logic. Early anvils had very small hardy holes (about 1/2" or 13mm square) so the hardy that fit was not very stout.

Others have suggested that the hardy was also called a "hack iron" and somehow this got slurred to "hackern" and then hardie. . . but both this and the above are pure speculation.

It is one of those mysteries such as are many names, it just IS.

hot rasping
Using a coarse file on hot iron or steel. The steel is usually anywhere from a dull red to a high black heat and the filing chips often come off ignited. It is a common blacksmith and farrier technique but is VERY hard on files.

A unit of the archaic old English system of weight measurement symbolized by CWT. Where:
One CWT (hundredweight) equals 112 pounds.
One quarter hundredweight equals 28 pounds.
One eighth hundredweight called a "stone" equals 14 pounds.
A long tonne = 20 hundredweights

Commonly used to make weight of old anvils. See Hundredweight anvil calculator

Element number 26, metallic. Symbol Fe (l. ferrum). Pure iron is a soft ductile metal. Unprotected it oxidizes (rusts) rapidly. Steel is iron with a small percentage of carbon (1.5 max) making it hardenable. Cast iron generally has 3 percent or greater carbon content and is very brittle and non-ductile. Wrought iron is pure iron crystals with thin layers of siliceous slag resulting in graininess similar to wood. Lack of carbon makes wrought iron unhardenable.

The word "iron" is used loosely to describe anything made of cast iron, steel or wrought iron. In blacksmithing forging steel is often called "pounding iron".

Average density 7.874 g/cm3, .2845 lbs/cuin, 491.56 lbs/cuft.

Los Alamos National Laboratory periodic table entry iron

One who has finished their education as an apprentice and is ready to be employed elsewhere. Historically the Journeyman traveled to other jobs to learn what could be learned and then moved on until ready to become a "Master". Many journeymen never become masters and simply remain skilled workers in their field.

Metric standard method of measuring absolute temperature.
Absolute zero = 0°K = -273.16°C.

open die forging
Process where forging is done on a power or forging hammer using general purpose dies that do not have "mold" impressions. Often simple hand held tooling such as fullers, swages, punches, hot cuts or temporary dies are used. The dies need to be open from all sides so that work and tools can be manipulated under the hammer. Small hammers up to about 1,000 pounds are considered open die hammers. However permanent closed dies may be installed on any hammer given the size of the work is within the its capacity. In a typical industrial operation you may have a team of four workers making an open die forging. The smith directs the work. The driver operates the hammer controls. Then a "hot iron ?" man that takes the hot steel from the forge and puts it under the hammer. This may be done by hand, supported by a jib crane or via a "manipulator" a machine like a fork lift that is used to handle the hot steel. And the last man (or men) is a tool handler that holds long handled tools on the work. There may also be a fifth man to brush scale off the dies or to swab them with lubricant. Like hand forging open die forging wastes little or no material.

peen or pein (pane, pene)
The rounded small end of a hammer opposite the face. May be round (a ball peen) or a straight wedge shape.

Current accepted spelling is peen, however, many authors and tool catalogs do not use this spelling. In Metal Working, by Paul N. Hasluck 1907, the author uses "pene" for the back sides of hammers. In Metal Techniques for Craftsmen, Oppi Untracht 1968, uses "pein" and give alternate spellings of "peen" and "pane" but in editing the index "peen" is used with (pein) as alternate. In The Art of Blacksmithing Alex Bealer 1969, uses "pein". Note that both these common and authoritative uses break the rule of I before E except after C.

My 1916 Webster's Unabridged Dictionary of the English Language gives "peen" with "pen, pinne and pane" as alternate derivatives. The Oxford English Dictionary gives "Pien" as an obsolete form of pane and pain. Under Peen it gives alternates of pene and pean, derived from the Norse, meaning to beat and draw out thin (related to metal working).

Piene, is an old word meaning a type of punishment where weights were piled on a prisoner until it created great pain. A form of torture.

SO, despite the I before E rule, my use and some current catalog use, the following are correct in this order,
Peen, Pein, Pene, and sometimes the archaic Pane.

penny weld
A penny weld is copper brazing similar to spelter The part is heated and fluxed, then the copper sprinkled on around the joint. The part is heated until the copper runs and then is removed from the fire to cool. The source of the copper often being pennies the word was applied to the method. However, modern American pennies have been copper clad zinc since 1983 and are not suitable for making a "penny" weld. Copper wire is now commonly used and actually is more convenient as a small piece can be wrapped around the part to be joined.

pig iron
A common term for cast iron or cast iron ingots. The term originated from the practice of casting ingots in triangular section troughs cut in the sand floor of foundries. A central trough fed smaller molds on its side like suckling pigs. Thus "pig iron".

The slender rectangular punch used by farriers to hot punch the nail hole in a horseshoe. The small round hole in London and American pattern anvils is used for this punching operation and is called the pritchell hole. Many farriers' anvils had two pritchell holes.

Liquid or gas used to cool a metal in heat treating. Water, brine, oil and air are common quenchants. Liquid salts and metals are also used.

See Quenchants FAQ

Official unit of angular measurement in the metric (SI) system. PI radians (3.1415. . .) = 180°

Absolute temperature measurment scale where each unit is equal to those of the Fahrenheit scale.

0°R = -459.69°F = -273.16°C = 0°K = Absolute Zero

In ironworking particularly forging, scale is the dark blue black grey oxide that forms on the surface or the iron, steel or stainless when heated to forging temperatures. Scale is essentially magnetic oxide of iron, Fe3O4. Other iron oxides include red iron oxide Fe2O3, and FeO another black oxide that is highly flammable.

Scale on steel can be a very thin layer to a heavy layer as much as 1/16" (1.5mm) thick or more. Scale is hard and abrasive causing tools to wear. Primitive oil and wax finishes are scale which when wetted looks black rather than blue grey.

Weld preparation. Adj. scarf, verb. to scarf. A scarf for forge welding is generally an upset and two tapered ends that overlap at the joint. The upset is to provide extra metal for finishing to shape so that the joint is not smaller than the surrounding metal. Normally one side of the joint is flat or convex and the other convex so that flux and swarf can squeeze out of the joint. In arc welding a scarf is the chamfering of edges of one or more pieces to make a "V" joint that is filled with filler metal making a full or near full penetration joint. There are as many types of scarf as there are joints.

Common mispronunciation of shut in "cold shut". See cold shut

shrink rule
A measuring rule or "scale" that has increments increased in size the amount that metal shrinks when making castings. A pattern is made using a shrink rule and the the resulting casting will be the correct size. They are made for iron, brass, bronze and aluminium.

In English units, shrinkage is given in fractions of an inch per foot. 1/8" per foot, 3/32" per foot and so on. A 12" shrink rule at 3/32" per foot will be 12-3/32" long.

When a pattern is made, then cast in one metal to use as a more durable pattern for another metal (or the same metal) then a "double shrink" allowance is made. In most cases this is done mathematically by the patternmaker.

The place the smith or blacksmith works, a blacksmith shop is a smithy. Often confused with smith or blacksmith.
  • French, atelier de maréchalerie
  • German, (die) Schmiede
  • Italian, officina del maniscalco
  • Spanish (la) herreriá
  • Swedish smedja

Spelter is an archaic term for zinc. It was a popular metal for making production sculpture castings in the late 1800's and early 1900's and they still go by the name spelter. Some are painted and others are brass plated and carefully patinated. Zinc is cheaper and much easier to cast than brass or bronze. Spelter statuary is "collectable" and the "value" is determined by the whims of the antique and collectable market.

Spelter is also a term used for brass powder used to fire braze iron or steel in a forge. The part is heated and fluxed, then the "spelter" sprinkled on around the joint. Modern smiths do something similar and call it a "penny weld".

Cast iron (not steel) of increased strength, obtained by using a large percentage of steel scrap with the pig iron. The quality varies, but if a known amount of good steel is added, like rail croppings, the resulting product will have more ductility and strength than cast iron alone. However, if large amounts of impure scrap is used the resulting product is not as good as high grade grey iron. Used for casters, machine frames and other items where toughness is needed in a cast product.

Iron with a small percentage of carbon. The amount of carbon determines the steel's hardenability. The more carbon the harder the steel can be made by heat treatment. "Mild steel" contains 0.18 to 0.20% carbon. Low carbon steels less, medium and high carbon steels more. "High" carbon steels start at roughly 0.75% carbon and may include up to about 1.5%. Alloy steels may have more carbon extending into the cast iron range at 2% to 2.5% max. Mild and low carbon steels are not considered hardenable for practical purposes but will harden to a small degree. Almost all steels contain some alloying ingredients (other metals) but are not called alloy steels unless the addition is significant or added on purpose.

Average density mild steel, 7.847 g/cm3, .2835 lbs/cuin, 489.89 lbs/cuft

Abbreviation for temporary, temperature or possibly but unlikely temper. Should not be used in metalworking discourse due to possible confusion.

The condition of substance, usually adjustable. In metals it the hardness resulting from the manufacturing process, heat treating, aging or working as in work hardening. In foundry sand it the level of moisture and clay that results in the ability of the sand to bond and hold shape. In ferrous alloys it is the hardness after heat treating. See tempering, heat treating.

Espaniol temperatura, French la température, German Temperatur, Italian temperatura.
Condition as regards heat or cold. Thermal energy measured in degrees as symbolized by °.

Units of measurement °F Fahrenheit, °C Celsius. Absolute - °R Rankine, °K Kelvin.

temper color
Colors produced by the oxidation of clean steel used to indicate temperatures during the tempering process. Standard temper color charts are only applicable to plain carbon steel. Alloying ingredients change the rate of oxidation making the charts inaccurate on alloy steels.

Temper colors are also used as a decorative finish or coloring of metal.

Verb, the adjustment of temper. In ferrous metallurgy tempering is the reheating of steel to some temperature below the hardening temperature after hardening in order to reduce the brittleness which also reduces the hardness. The tempering range for steel is from 350°F (177°C) to as high as 1350°F (732°C). It is recommended to temper almost all ferrous metals after hardening. See heat treating. In non-ferrous metals the temper (hardness) is adjusted by heat treating, aging or work hardening. See references on specific metals for methods.

Division of Big Three Industries that manufactures Tempil temperature indicating crayons commonly called "tempil sticks". Also the distributor of the popular wall chart, the Tempil Guide to Ferrous Metallurgy.

Element number 50, symbol Sn, a metal (Latin, stannum). A silver white soft ductile metal occasionally found in its native state. Tin is one of the earliest known metals and was used both in its pure form as well as an alloying ingredient by the ancients. Pure tin was used by the Ancient Greeks as parts of light tight fitting armor such as shin guards (Homer's, Illiad. Tin is the secondary metal in the alloy bronze and the primary metal in solder along with lead (Pb). Tin is corrosion resistant and has a very low melting point as well as an affinity for adhering to other metals, thus tin plate, tin cans, babbitt and solder.

Average density of tin, 7.298 g/cm3, .2637 lbs/cuin, 455.62 lbs/cuft

Los Alamos National Laboratory periodic table entry tin

trumming or trumming cord
Jeweler's term. A method of using a cord charged with abrasives to cut, grind or polish. A trumming cord is made of any size string or cord with something tacky to hold the abrasive which is then applied as dust. Braided cords are preferred because they do not unravel. Abrasive can also be applied directly from stick buffing and polishing compounds which are already in a was matrix.

The ancients used a similar process using rope or cord to cut stone. The modern method uses wire.

Commercial abrasive cord is manufactured similar to abrasive cloth or belting.

The nozzle end of a pipe or tube that blows air onto a forge or furnace fire. Early tuyeres were tapered ceramic tubes that were buried in the earth or clay bottom of a forge or furnace (smelting, glass blowers or other). A common British type for side blast forges has a double wall and is water cooled. Modern bottom blown coal forge tuyeres often include an ash dump and a "clinker breaker". In smelting furnaces tuyeres have a door (sometimes with an inspection window) for cleaning out the tuyere if it becomes clogged.

In forging, to increase section and reduce length by hammering or pressing on the end of a bar. An "upsetter" is a mechanical or hydraulic machine for producing larger masses on the end of a bar by upsetting.

A term used to describe the perfect unobtainable metal. It is the substance of mythical swords that never dull and unbreakable weapons. It is akin to fictional materials like Adamantium and Kryptonite.

A foliated mineral employed in making plaster board and sound insulation and as a soil lightener in gardening. The mineral is an alteration of biotite and other micas. Vermiculite is used as an annealing medium in some blacksmith shops. However, it tends to absorb moisture reducing its effectiveness and under certain conditions may fuse to the work. Wood ash or quick lime are traditional mediums for this application.

Free Moisture, Maximum0.5%
pH (of water slurry)7.0-9.5
Specific Gravity2.5
Expanded Bulk Density (normal)4-10 lb/ft3
Mesh Sizes (normal)2-40 mesh and finer
Fusion Point2200-2400F
Specific Heat1.08 kJ/kg.K
Thermal Conductivity.27-.41

See for more information.


See Blacksmith

wrought iron
Wrought iron is pure iron crystals with thin layers of siliceous slag resulting in graininess similar to wood. Lack of carbon makes wrought iron unhardenable but very ductile. The graininess requires special handling in forging, cutting and punching. Wrought was the product of early bloomeries and was the primary ductile form of iron for several millennia. It was last manufactured as "charcoal iron" in Sweden in 1968. It was last manufactured by the Bayer process in the U.S. In this process nearly pure iron was created in the blast furnace removing all carbon. The a silicon slag was added to the liquid iron and the mixture rolled the same way as modern steel.

Wrought iron is also the description of decorative ironwork that is made of any metal including wrought iron, steel, cast iron and aluminium. Wrought iron is also used to describe low carbon steel pipe.

See iron
See Wrought Iron FAQ

Element number 30, symbol Zn, a metal (German, Zink). A bluish white ductile metal known to the ancients in brass but was not produced separately until the 18th century. Zinc is the secondary metal in the alloy brass, naval brass, alloy C28000 being 60% copper 39.2% zinc and 2% tin. Zinc is used to make hard varieties of aluminium and aluminium is used to make light strong zinc casting alloys. The United States penny has been made out of copper clad zinc since 1983.

Average density of zinc, 7.133 g/cm3, .2577 lbs/cuin, 445.30 lbs/cuft

Los Alamos National Laboratory periodic table entry zinc

Description (template)

Average density of , g/cm3, lbs/cuin, lbs/cuft

Capitalization rule (SI English)
SI (System International, IE; metric) units of measurment named for a person are capitalized while others are not. The same rule should be applied to traditional units.

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